The present invention relates to a dental drill narrowing up to its tip, of the type comprising helicoidal flutes exhibiting on their edges cutting lips for the drilling of the dental canals.
Dental drills with one helicoidal flute have been known for a long time.
Dental drills with two helicoidal flutes have been described, for example, in French Patent Application No. 80.20893.
The drills described in that application exhibit particularly the disadvantage that, in a flattened canal, there is a danger of the tip slipping to the side.
On the other hand, these drills are of constant pitch, which gives them excessive rigidity.
Since moreover the drills of this type are intended to be mounted on a dentistry tool imparting to them an alternating rotary movement of approximately one quarter turn, the drilling executed with a drill with one or two flutes will be inadequate or imperfect because the drill will have a tendency to screw into the asperities of the canal.